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An approach to estimating sediment transport along the Delaware--Maryland coast is described. Wave information study (second generation model, WISWAVE 2.0) hindcast frequency-direction spectra from 1980 to 1999 are used to generate a radiation stress-conserving angle for bringing offshore waves to breaking to estimate alongshore sediment transport. Using standard values for the coefficients in the United States Army Corps of Engineers' Coastal Engineering Research Center (CERC) equation yields 20-year mean alongshore sediment transport rates between 470,942 and -517,088 [m.sup.3]/year depending on alongshore location after shoaling waves to shore. Interannual variability is large with SDs between 95,078 and 241,313 [m.sup.3]/year again depending on alongshore location. Alongshore sediment transport rate estimates are commensurate with past studies using WIS data but overpredict the typically cited value of ~100,000 [m.sup.3]/year near Indian River Inlet, Delaware based on sediment budget data by a factor of 3-4. This overestimation could be compensated for by altering the constant K in the CERC transport equation or slight variations in the shoreline normal. The yearly estimates of the nodal point location where the sediment transport rate reverses direction were just south of the Delaware-Maryland border. The nodal point experienced interannual variability on the order of several thousand meters and is mainly attributed to the interannual variability in wave forcing. It is found that estimating alongshore sediment transport rates from offshore wave data are dependent on proper preservation of the radiation stress (using a radiation stress-conserving wave angle) and accurate determination of the shoreline normal. DOI: 10.1061/(ASCE)WW.1943-5460.0000034 CE Database subject headings: Beaches; Water waves; Sediment transport; Delaware; Maryland. Author keywords: Beach.

The practice of environmental public health (EPH)--ensuring food, water, and sanitation protection--is the traditional cornerstone of public health. Demands on the EPH infrastructure have broadened, however, to involve issues such as chemical and physical hazards in the environment, the role of the built environment in health, and disaster preparedness. Maryland, with its varied geography and population densities, faces many of the EPH challenges that are present elsewhere throughout the nation. A strong and stable EPH workforce is an essential ingredient in addressing these challenges. Yet significant workforce obstacles exist, including recruitment shortfalls, inability to retain qualified staff, impending retirements, inadequate training opportunities, insufficient compensation, and the absence of a robust career advancement pathway. Recognizing the importance of EPH protection for Maryland's future, state and local agencies and academic institutions are working collaboratively to address EPH challenges. Much progress has been made: Communication and interaction between state and local agencies have been strengthened; practitioners and academic institutions have collaborated to improve EPH training opportunities; and workforce development efforts have been made to address recruitment and retention challenges. Although there have been significant accomplishments, much work remains. It is imperative that these efforts continue and that they be supported at all levels of government. Coordination and communication, as well as the training, recruitment, and retention of the workforce, are critical to a strong and responsive EPH infrastructure., Introduction According to Healthy People 2010, a strong public health infrastructure is necessary for fulfillment of the mission of public health, which includes preventing epidemics and the spread of disease, [...]

Annual bluegrass (Poa annua L.; ABG) can be a major weed problem in golf course turf, Research-based information on the seasonal emergence patterns of ABG is limited. The objectives of this four-year field study were (i) to determine seasonal ABG emergence patterns in Maryland, (ii) to determine peak period(s) of ABG emergence, and (iii) to determine the date and estimated percentage of seedlings emerged when the rate of emergence declines. Annual bluegrass seedlings were found to emerge between August and May in two Maryland golf course roughs. A majority (50-70%) of seedling emergence occurred between late September and mid-October, and peak germination generally was observed in early October. The linear increase in ABG seedling emergence generally ended by early November; however, 24% of all seedlings emerged between November and May. No major ABG emergence cycles were observed during the spring in any year. Mean daily temperatures generally were [less than or equal to] 20[degrees]C during peak ABG emergence periods, and germination was stimulated by precipitation. Since the genetic diversity of ABG is well known, these findings may only be applicable to Maryland and regions with similar environmental conditions.

ABSTRACT In 1997, Maryland had no available ambient Federal Reference Method data on particulate matter less than 2.5 µm in aerodynamic diameter ([PM.sub.2.5]), but did have annual ambient data for [...]

In July 1997, in response to health studies showing that cumulative exposure even to low levels of ozone can have adverse health effects, the U.S. Environmental Protection Agency promulgated a more stringent National Ambient Air Quality Standard for ground-level ozone. One-hour average ozone concentrations ranging from 0.07 parts per million (ppm) to 0.09 ppm were considered as alternative health-protective standards during the regulatory process. To determine the extent to which resident and tourist populations on the Lower Eastern Shore of Maryland are exposed to potentially harmful concentrations of ozone, this study examines state and local monitoring site (SLAMS) data from 1985 to 1988, the only years in which monitoring was performed on the Lower Eastern Shore. The results show that hourly concentrations exceeded 0.07 ppm (which the Clean Air Science Advisory Committee has recommended be considered a health-significant level) in 1,132 instances. In 479 instances, concentrations were above 0.08 ppm, and in 193 instances, concentrations were above 0.09 ppm. The total number of days on which the hourly ozone maximum exceeded 0.07 ppm was 185. On 102 days, the maximum was above 0.08 ppm, and on 48 days it was above 0.09 ppm. Ozone levels exceeded an eight-hour average concentration of 0.08 ppm a total of 52 days during the study period. Nevertheless, under the new standard, the Lower Eastern Shore SLAMS would have achieved compliance. Comparisons with ozone levels in the Baltimore-Washington corridor show that extrapolation from monitoring results in these urban areas may not predict high ozone levels on the Eastern Shore. Consequently, local monitoring in rural areas is critical to the provision of accurate local public health information and the development of forecast models specific for the area., Introduction Ground level ozone, a powerful 'oxidant, is a main component of smog and the most toxic of the six "criteria air pollutants" regulated by the U.S. Environmental Protection Agency [...]

The distribution and abundance of amphibians and reptiles in forest stands subjected to salvage cutting and prescribed burning were compared with their unmanaged counterparts. The study was conducted on the Atlantic coastal plain at Chesapeake Farms near Chestertown, Maryland. Three herpetofaunal trapping arrays were systematically located in each of four forest stand types: hardwood (Hardwood), cut-over hardwood (Cut), mixed pine-hardwood (Pine) and prescribed burn pine (Burn). A total of 3931 individuals representing 29 species were captured in 30,540 trap nights during the spring and summer 1992 and 1993. Felling of hardwoods and prescribed burning of pine resulted in similar responses from the herpetofaunal communitites; Hardwood had the most distinctive herpetofaunal community of the four stands. Adults and young-of-the-year (YOY) of six amphibian species were significantly more abundant in Hardwood than Cut. Only one amphibian species, Pseudacris triseriata, was less abundant in Hardwood than Cut. Total ranid captures did not differ between Hardwood and Cut. Snake and total reptile captures, and Elaphe obsoleta and Eumeces faciatus abundances were significantly less in Hardwood than Cut. Hardwood also had fewer small mammals than Cut, particularly Microtus pennsylvanicus and Zapus hudsonius, that might serve as prey for large snakes. Adults of four amphibian species, YOY of five amphibian species, and three reptiles (Carphophis amoenus, Storeria dekayi and Thamnophis sirtalis) were significantly more abundant in Pine than Burn; two reptile species (Coluber constrictor and Lampropeltis getula) were significantly less abundant. Potential small mammal prey of the latter two snakes were not significantly different between Pine and Burn; however, Zapus hudsonius was less abundant in Pine than in Burn. More amphibians were captured in Hardwood and Pine stands than in their respective logged and burned counterparts. The trend for reptiles tended to depend on the mix of species present and their habitat preferences. Greater canopy cover and depth of leaf litter in Hardwood and Pine stands likely had a moderating effect on temperature and helped to maintain a moist microenvironment for mesophilic species. Disturbance of a small patch of forest could locally decrease herpetofaunal diversity, but diversity on a much larger scale would likely increase., INTRODUCTION Logging and prescribed burning are two commonly used forest management practices that modify forest habitat by changing vegetation composition and structure, and which have been shown to alter the [...]

The economic and conservation factors associated with low cost land acquisitions are discussed by focusing on Maryland.

Proposals for the inclusion of permanently submersed materials in soil taxonomic systems have periodically been put forth since some time in the mid 1800s. The proposals were largely conceptual in nature, relying more on subjective reasoning rather than analytical and field data. Advances in computer and global positioning technology, and the continuing development of the discipline of pedology provided the opportunity to examine shallow water estuarine sediments within a pedological framework. Morphological and analytical data from 85 1.5- to 2.0-m profiles from Sinepuxent Bay, Maryland, indicate that the four pedogenic processes of additions, losses, transformations, and transfers outlined in the generalized theory of soil genesis are active in a subaqueous environment. The evidence of pedogenic processes includes the addition of biogenic calcium carbonate (shells), organic fragments, and organic matter; the loss of organic matter and surficial material; the transfer of oxygen through diffusion and bioturbation processes; and the transformation of humic substances and sulfur (sulfidization). The change in the concept of estuarine substrates from sediment to soil has significant ramifications for pedologists, ecologists, estuarine researchers, and government agencies involved in soil resource inventory and estuarine restoration programs. Application of these concepts could help further our understanding of the relationships between subaqueous soil distribution and submersed aquatic vegetation (SAV); clam, scallop, and oyster habitat; and dredge sites with potential acid-sulfate weathering. This work resulted in a change to the definition of soil in Soil Taxonomy to include subaqueous soils that are capable of or presently support rooted SAV.